Internet DRAFT - draft-ietf-6lo-nfc
draft-ietf-6lo-nfc
6Lo Working Group Y. Choi, Ed.
Internet-Draft ETRI
Intended status: Standards Track Y-G. Hong
Expires: 7 September 2023 Daejon Univ
J-S. Youn
Dongeui Univ
6 March 2023
Transmission of IPv6 Packets over Near Field Communication
draft-ietf-6lo-nfc-22
Abstract
Near Field Communication (NFC) is a set of standards for smartphones
and portable devices to establish radio communication with each other
by touching them together or bringing them into proximity, usually no
more than 10 cm apart. NFC standards cover communications protocols
and data exchange formats, and are based on existing radio-frequency
identification (RFID) standards including ISO/IEC 14443 and FeliCa.
The standards include ISO/IEC 18092 and those defined by the NFC
Forum. The NFC technology has been widely implemented and available
in mobile phones, laptop computers, and many other devices. This
document describes how IPv6 is transmitted over NFC using 6LoWPAN
techniques.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 7 September 2023.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 3
3. Overview of Near Field Communication Technology . . . . . . . 4
3.1. Peer-to-peer Mode of NFC . . . . . . . . . . . . . . . . 4
3.2. Protocol Stack of NFC . . . . . . . . . . . . . . . . . . 4
3.3. NFC-enabled Device Addressing . . . . . . . . . . . . . . 6
3.4. MTU of NFC Link Layer . . . . . . . . . . . . . . . . . . 6
4. Specification of IPv6 over NFC . . . . . . . . . . . . . . . 7
4.1. Protocol Stack . . . . . . . . . . . . . . . . . . . . . 7
4.2. Stateless Address Autoconfiguration . . . . . . . . . . . 8
4.3. IPv6 Link-Local Address . . . . . . . . . . . . . . . . . 8
4.4. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 9
4.5. Dispatch Header . . . . . . . . . . . . . . . . . . . . . 10
4.6. Header Compression . . . . . . . . . . . . . . . . . . . 10
4.7. Fragmentation and Reassembly Considerations . . . . . . . 11
4.8. Unicast and Multicast Address Mapping . . . . . . . . . . 11
5. Internet Connectivity Scenarios . . . . . . . . . . . . . . . 12
5.1. NFC-enabled Device Network Connected to the Internet . . 12
5.2. Isolated NFC-enabled Device Network . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
NFC is a set of short-range wireless technologies, typically
requiring a distance between sender and receiver of 10 cm or less.
NFC operates at 13.56 MHz, and at rates ranging from 106 kbps to 424
kbps, as per the ISO/IEC 18000-3 air interface [ECMA-340]. NFC
builds upon RFID systems by allowing two-way communication between
endpoints. NFC always involves an initiator and a target; the
initiator actively generates an RF field that can power a passive
target. This enables NFC targets to take very simple form factors,
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such as tags, stickers, key fobs, or cards, while avoiding the need
for batteries. NFC peer-to-peer communication is possible, provided
that both devices are powered.
NFC has its very short transmission range of 10 cm or less, so the
other hidden NFC devices behind outside the range cannot receive NFC
signals. Therefore, NFC often regarded as a secure communications
technology.
In order to benefit from Internet connectivity, it is desirable for
NFC-enabled devices to support IPv6, considering its large address
space, along with tools for unattended operation, among other
advantages. This document specifies how IPv6 is supported over NFC
by using IPv6 over Low-power Wireless Personal Area Network (6LoWPAN)
techniques [RFC4944], [RFC6282], [RFC6775]. 6LoWPAN is suitable,
considering that it was designed to support IPv6 over IEEE 802.15.4
networks [IEEE802.15.4], and some of the characteristics of the
latter are similar to those of NFC.
2. Conventions and Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
This specification requires readers to be familiar with all the terms
and concepts that are discussed in "IPv6 over Low-Power Wireless
Personal Area Networks (6LoWPANs): Overview, Assumptions, Problem
Statement, and Goals" [RFC4919], "Transmission of IPv6 Packets over
IEEE 802.15.4 Networks" [RFC4944], "Neighbor Discovery Optimization
for IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs)
[RFC6775].
6LoWPAN Node (6LN):
A 6LoWPAN node is any host or router participating in a LoWPAN.
This term is used when referring to situations in which either
a host or router can play the role described.
6LoWPAN Router (6LR):
An intermediate router in the LoWPAN that is able to send and
receive Router Advertisements (RAs) and Router Solicitations
(RSs) as well as forward and route IPv6 packets. 6LoWPAN
routers are present only in route-over topologies.
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6LoWPAN Border Router (6LBR):
A border router located at the junction of separate 6LoWPAN
networks or between a 6LoWPAN network and another IP network.
There may be one or more 6LBRs at the 6LoWPAN network boundary.
A 6LBR is the responsible authority for IPv6 prefix propagation
for the 6LoWPAN network it is serving. An isolated LoWPAN also
contains a 6LBR in the network, which provides the prefix(es)
for the isolated network.
3. Overview of Near Field Communication Technology
This section presents an overview of NFC, focusing on the
characteristics of NFC that are most relevant for supporting IPv6.
NFC enables simple, two-way, interaction between two devices,
allowing users to perform contactless transactions, access digital
content, and connect electronic devices with a single touch. NFC
utilizes key elements in existing standards for contactless card
Technology, such as ISO/IEC 14443 A&B and JIS-X 6319-4. NFC allows
devices to share information at a distance up to 10 cm with a maximum
physical layer bit rate of 424 kbps.
3.1. Peer-to-peer Mode of NFC
NFC defines three modes of operation: card emulation, peer-to-peer,
and reader/writer. Only the peer-to-peer mode allows two NFC-enabled
devices to communicate with each other to exchange information
bidirectionally. The other two modes do not support two-way
communications between two devices. Therefore, the peer-to-peer mode
MUST used for IPv6 over NFC.
3.2. Protocol Stack of NFC
NFC defines a protocol stack for the peer-to-peer mode (Figure 1).
The peer-to-peer mode is offered by the Activities Digital Protocol
at the NFC Physical Layer. The NFC Logical Link Layer comprises the
Logical Link Control Protocol (LLCP), and when IPv6 is used over NFC,
it also includes an IPv6-LLCP Binding. IPv6 and its underlying
adaptation Layer (i.e., IPv6-over-NFC adaptation layer) are placed
directly on the top of the IPv6-LLCP Binding. An IPv6 datagram is
transmitted by the Logical Link Control Protocol (LLCP) with
guaranteed delivery, two-way transmission of information between the
peer devices.
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+----------------------------------------+ - - - - - - - - -
| Logical Link Control Protocol | NFC Logical
| (LLCP) | Link Layer
+----------------------------------------+ - - - - - - - - -
| Activities |
| Digital Protocol | NFC Physical
+----------------------------------------+ Layer
| RF Analog |
+----------------------------------------+ - - - - - - - - -
Figure 1: Protocol Stack of NFC
The LLCP consists of Logical Link Control (LLC) and MAC Mapping. The
MAC Mapping integrates an existing RF protocol into the LLCP
architecture. The LLC contains three components (Link Management,
Connection-oriented Transmission, and Connectionless Transmission).
The Link Management is responsible for serializing all connection-
oriented and connectionless LLC PDU (Protocol Data Unit) exchanges
and for aggregation and disaggregation of small PDUs. The
Connection-oriented Transmission is responsible for maintaining all
connection-oriented data exchanges including connection set-up and
termination. However, NFC links do not guarantee perfect wireless
link quality, so some type of delays or variation in delay would be
expected in any case. The Connectionless Transmission is responsible
for handling unacknowledged data exchanges.
In order to send an IPv6 packet over NFC, the packet MUST be passed
down to the LLCP layer of NFC and carried by an Information Field in
an LLCP Protocol Data Unit (I PDU). The LLCP does not support
fragmentation and reassembly. For IPv6 addressing or address
configuration, the LLCP MUST provide related information, such as
link layer addresses, to its upper layer. The LLCP to IPv6 protocol
binding MUST transfer the Source Service Access Point (SSAP) and
Destination Service Access Point (DSAP) value to the IPv6 over NFC
adaptation layer. SSAP is a Logical Link Control (LLC) address of
the source NFC-enabled device with a size of 6 bits, while DSAP means
an LLC address of the destination NFC-enabled device. Thus, SSAP is
a source address, and DSAP is a destination address.
In addition, NFC links and host do not need to consider IP header
bits for QoS signaling, or utilize these meaningfully.
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3.3. NFC-enabled Device Addressing
According to [LLCP-1.4], NFC-enabled devices have two types of 6-bit
addresses (i.e., SSAP and DSAP) to identify service access points.
Several service access points can be installed on a NFC device.
However, the SSAP and DSAP can be used as identifiers for NFC link
connections with the IPv6 over NFC adaptation layer. Therefore, the
SSAP can be used to generate an IPv6 interface identifier. Address
values between 00h and 0Fh of SSAP and DSAP are reserved for
identifying the well-known service access points, which are defined
in the NFC Forum Assigned Numbers Register. Address values between
10h and 1Fh are assigned by the local LLC to services registered by
local service environment. In addition, address values between 0x2
and 0x3f are assigned by the local LLC as a result of an upper layer
service request. Therefore, the address values between 0x2 and 0x3f
can be used for generating IPv6 interface identifiers.
3.4. MTU of NFC Link Layer
As mentioned in Section 3.2, when an IPv6 packet is transmitted, the
packet MUST be passed down to LLCP of NFC and transported to an I PDU
of LLCP of the NFC-enabled peer device.
The information field of an I PDU contains a single service data
unit. The maximum number of octets in the information field is
determined by the Maximum Information Unit (MIU) for the data link
connection. The default value of the MIU for I PDUs is 128 octets.
The local and remote LLCs each establish and maintain distinct MIU
values for each data link connection endpoint. Also, an LLC may
announce a larger MIU for a data link connection by transmitting an
optional Maximum Information Unit Extension (MIUX) parameter within
the information field. If no MIUX parameter is transmitted, the MIU
value is 128 bytes. Otherwise, the MTU size in NFC LLCP MUST be
calculated from the MIU value as follows:
MTU = MIU = 128 + MIUX.
According to [LLCP-1.4], Figure 2 shows an example of the MIUX
parameter TLV. The Type and Length fields of the MIUX parameter TLV
have each a size of 1 byte. The size of the TLV Value field is 2
bytes.
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0 0 1 2 3
0 8 6 1 1
+----------+----------+-----+-----------+
| Type | Length | Value |
+----------+----------+-----+-----------+
| 0x02 | 0x02 | 0x0 | 0x480 |
+----------+----------+-----+-----------+
Figure 2: Example of MIUX Parameter TLV
When the MIUX parameter is used, the TLV Type field is 0x02 and the
TLV Length field is 0x02. The MIUX parameter is encoded into the
least significant 11 bits of the TLV Value field. The unused bits in
the TLV Value field is set to zero by the sender and ignored by the
receiver. The maximum possible value of the TLV Value field is
0x7FF, and the maximum size of the LLCP MTU is 2175 bytes. As per
the present specification [LLCP-1.4], the MIUX value MUST be 0x480 to
support the IPv6 MTU requirement (of 1280 bytes) [RFC8200].
4. Specification of IPv6 over NFC
NFC technology has requirements owing to low power consumption and
allowed protocol overhead. 6LoWPAN standards [RFC4944], [RFC6775],
and [RFC6282] provide useful functionality for reducing the overhead
of IPv6 over NFC. This functionality consists of link-local IPv6
addresses and stateless IPv6 address auto-configuration (see
Section 4.2 and Section 4.3), Neighbor Discovery (see Section 4.4)
and header compression (see Section 4.6).
4.1. Protocol Stack
Figure 3 illustrates the IPv6 over NFC protocol stack. Upper layer
protocols can be transport layer protocols (e.g., TCP and UDP),
application layer protocols, and others capable of running on top of
IPv6.
+----------------------------------------+
| Upper Layer Protocols |
+----------------------------------------+
| IPv6 |
+----------------------------------------+
| Adaptation Layer for IPv6 over NFC |
+----------------------------------------+
| NFC Logical Link Layer |
+----------------------------------------+
| NFC Physical Layer |
+----------------------------------------+
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Figure 3: Protocol Stack for IPv6 over NFC
The adaptation layer for IPv6 over NFC supports neighbor discovery,
stateless address auto-configuration, header compression, and
fragmentation & reassembly, based on 6LoWPAN. Note that 6LoWPAN
Header compression [RFC6282] does not define header compression for
TCP. The latter can still be supported over IPv6 over NFC, albeit
without the performance optimization of header compression.
4.2. Stateless Address Autoconfiguration
An NFC-enabled device performs stateless address autoconfiguration as
per [RFC4862]. A 64-bit Interface identifier (IID) for an NFC
interface is formed by utilizing the 6-bit NFC SSAP (see
Section 3.3). In the viewpoint of address configuration, such an IID
should guarantee a stable IPv6 address during the course of a single
connection, because each data link connection is uniquely identified
by the pair of DSAP and SSAP included in the header of each LLC PDU
in NFC.
Following the guidance of [RFC7136], interface identifiers of all
unicast addresses for NFC-enabled devices are 64 bits long and
constructed by using the generation algorithm of random (but stable)
identifier (RID) [RFC7217].
The RID is an output which is created by the F() algorithm with input
parameters. One of the parameters is Net_Iface, and NFC Link Layer
address (i.e., SSAP) MUST be a source of the Net_Iface parameter.
The 6-bit address of SSAP of NFC is short and easy to be targeted by
attacks of third party (e.g., address scanning). The F() algorithm
with SHA-256 can provide secured and stable IIDs for NFC-enabled
devices. In addition, an optional parameter, Network_ID is used to
increase the randomness of the generated IID with NFC link layer
address (i.e., SSAP). The secret key SHOULD be of at least 128 bits.
It MUST be initialized to a pseudo-random number [RFC4086].
4.3. IPv6 Link-Local Address
The IPv6 link-local address for an NFC-enabled device is formed by
appending the IID to the prefix fe80::/64, as depicted in Figure 4.
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0 0 0 1
0 1 6 2
0 0 4 7
+----------+------------------+----------------------------+
|1111111010| zeros | Interface Identifier |
+----------+------------------+----------------------------+
. .
. <- - - - - - - - - - - 128 bits - - - - - - - - - - - -> .
. .
Figure 4: IPv6 link-local address in NFC
The "Interface Identifier" can be a random and stable IID.
4.4. Neighbor Discovery
Neighbor Discovery Optimization for 6LoWPANs ([RFC6775]) describes
the neighbor discovery approach in several 6LoWPAN topologies, such
as mesh topology. NFC supports mesh topologies, but most of all
applications would use a simple multi-hop network topology or
directly connected peer-to-peer network because NFC RF range is very
short.
* When an NFC 6LoWPAN Node (6LN) is directly connected to an 6LBR,
the 6LN MUST register its address with the 6LBR by sending
Neighbor Solicitation (NS) with the Extended Address Registration
Option (EARO) [RFC8505], and Neighbor Advertisement (NA) is
started. When the 6LN and 6LBR are linked each other, an address
is assigned to the 6LN. In this process, Duplicate Address
Detection (DAD) is not required.
* When two or more NFC LNs are connected to the 6LBR, two cases of
topologies can be formed. One is a multi-hop topology, and the
other is a star topology based on the 6LBR. In multi-hop
topology, LNs which have two or more links with neighbor nodes may
act as routers. In star topology, any of LNs can be a router.
* For receiving Router Solicitations and sending Router
Advertisements, the NFC 6LNs MUST follow Sections 5.3 and 5.4 of
[RFC6775].
* When a NFC device is a 6LoWPAN Router (6LR) or a 6LBR, the NFC
device MUST follow Section 6 and 7 of [RFC6775].
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4.5. Dispatch Header
All IPv6-over-NFC encapsulated datagrams are prefixed by an
encapsulation header stack consisting of a Dispatch value
[IANA-6LoWPAN]. The only sequence currently defined for IPv6-over-
NFC MUST be the LOWPAN_IPHC compressed IPv6 header (see Section 4.6)
header followed by payload, as depicted in Figure 5 and Figure 6.
+---------------+---------------+--------------+
| IPHC Dispatch | IPHC Header | Payload |
+---------------+---------------+--------------+
Figure 5: A IPv6-over-NFC Encapsulated LOWPAN_IPHC Compressed
IPv6 Datagram
The dispatch value (length: 1 octet) is treated as an unstructured
namespace. Only a single pattern is used to represent current IPv6-
over-NFC functionality.
+------------+--------------------+-----------+
| Pattern | Header Type | Reference |
+------------+--------------------+-----------+
| 01 1xxxxx | LOWPAN_IPHC | [RFC6282] |
+------------+--------------------+-----------+
Figure 6: Dispatch Values
Other IANA-assigned 6LoWPAN Dispatch values do not apply to this
specification.
4.6. Header Compression
Header compression as defined in [RFC6282], which specifies the
compression format for IPv6 datagrams on top of IEEE 802.15.4, is
REQUIRED in this document as the basis for IPv6 header compression on
top of NFC. All headers MUST be compressed according to RFC 6282
encoding formats.
Therefore, IPv6 header compression in [RFC6282] MUST be implemented.
Further, implementations MUST also support Generic Header Compression
(GHC) of [RFC7400].
If a 16-bit address is required as a short address, it MUST be formed
by padding the 6-bit NFC SSAP (NFC link-layer node address) to the
left with zeros as shown in Figure 7.
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0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Padding(all zeros)| NFC Addr. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: NFC short address format
4.7. Fragmentation and Reassembly Considerations
IPv6-over-NFC MUST NOT use fragmentation and reassembly (FAR) at the
adaptation layer for the payloads as discussed in Section 3.4. The
NFC link connection for IPv6 over NFC MUST be configured with an
equivalent MIU size to support the IPv6 MTU requirement (of 1280
bytes). To this end, the MIUX value is 0x480.
4.8. Unicast and Multicast Address Mapping
The address resolution procedure for mapping IPv6 non-multicast
addresses into NFC link-layer addresses follows the general
description in Section 4.6.1 and 7.2 of [RFC4861], unless otherwise
specified.
The Source/Target link-layer Address option has the following form
when the addresses are 6-bit NFC SSAP/DSAP (NFC link-layer node
addresses).
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length=1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+- Padding (all zeros) -+
| |
+- +-+-+-+-+-+-+
| | NFC Addr. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: Unicast address mapping
Option fields:
Type:
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- 1: for Source Link-layer address.
- 2: for Target Link-layer address.
Length:
- This is the length of this option (including the type and
length fields) in units of 8 bits. The value of this field is
1 for 6-bit NFC node addresses.
NFC address:
- The 6-bit address in canonical bit order. This is the unicast
address the interface currently responds to.
The NFC Link Layer does not support multicast. Therefore, packets
are always transmitted by unicast between two NFC-enabled devices.
Even in the case where a 6LBR is attached to multiple 6LNs, the 6LBR
cannot do a multicast to all the connected 6LNs. If the 6LBR needs
to send a multicast packet to all its 6LNs, it has to replicate the
packet and unicast it on each link. However, this is not energy-
efficient, and the central node, which is battery-powered, must take
particular care of power consumption. To further conserve power, the
6LBR MUST keep track of multicast listeners at NFC link-level
granularity (not at subnet granularity), and it MUST NOT forward
multicast packets to 6LNs that have not registered as listeners for
multicast groups the packets belong to. In the opposite direction, a
6LN always has to send packets to or through the 6LBR. Hence, when a
6LN needs to transmit an IPv6 multicast packet, the 6LN will unicast
the corresponding NFC packet to the 6LBR.
5. Internet Connectivity Scenarios
5.1. NFC-enabled Device Network Connected to the Internet
Figure 9 illustrates an example of an NFC-enabled device network
connected to the Internet. The distance between 6LN and 6LBR is
typically 10 cm or less. For example, a laptop computer that is
connected to the Internet (e.g. via Wi-Fi, Ethernet, etc.) may also
support NFC and act as a 6LBR. Another NFC-enabled device may run as
a 6LN and communicate with the 6LBR, as long as both are within each
other's range.
NFC link
6LN ------------------- 6LBR -------( Internet )--------- CN
. . .
. <- - - - Subnet - - -> . < - - - IPv6 connection - - -> .
. . to the Internet .
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Figure 9: NFC-enabled device network connected to the Internet
Two or more 6LNs may be connected with a 6LBR, but each connection
uses different IPv6 prefix. The 6LBR is acting as a router and
forwarding packets between 6LNs and the Internet. Also, the 6LBR
MUST ensure address collisions do not occur because the 6LNs are
connected to the 6LBR like a start topology, so the 6LBR checks
whether IPv6 addresses are duplicate or not, since 6LNs need to
register their addresses with the 6LBR.
5.2. Isolated NFC-enabled Device Network
In some scenarios, the NFC-enabled device network may permanently be
a simple isolated network as shown in the Figure 10.
6LN 6LN - - - - -
| | .
NFC link - >| NFC link - >| .
| | .
6LN ---------------------- 6LR ---------------------- 6LR Subnet
. NFC link NFC link | .
. | .
. NFC link - >| .
. 6LN - - - - -
. .
. < - - - - - - - - - - Subnet - - - - - - - - - - > .
Figure 10: Isolated NFC-enabled device network
In multihop (i.e., more complex) topologies, the 6LR can also do the
same task, but then Duplicate Address Detection (DAD) requires the
extensions for multihop networks such as the ones in [RFC6775].
6. IANA Considerations
There are no IANA considerations related to this document.
7. Security Considerations
Neighbor Discovery in unencrypted wireless device networks may be
susceptible to various threats as described in [RFC3756].
Per the NFC Logical Link Control Protocol [LLCP-1.4]:
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* LLCP of NFC provides protection of user data to ensure
confidentiality of communications. The confidentiality mechanism
involves the encryption of user service data with a secret key
that has been established during link activation.
* LLCP of NFC has two modes (i.e., ad-hoc mode and authenticated
mode) for secure data transfer. Ad-hoc secure data transfer can
be established between two communication parties without any prior
knowledge of the communication partner. Ad-hoc secure data
transfer can be vulnerable to Man-In-The-Middle (MITM) attacks.
Authenticated secure data transfer provides protection against
Man-In-The-Middle (MITM) attacks. In the initial bonding step,
the two communicating parties store a shared secret along with a
Bonding Identifier.
* For all subsequent interactions, the communicating parties re-use
the shared secret and compute only the unique encryption key for
that session. Secure data transfer is based on the cryptographic
algorithms defined in the NFC Authentication Protocol [NAP-1.0].
Furthermore, NFC is considered by many to offer intrinsic security
properties due to its short link range. When interface identifiers
(IIDs) are generated, devices and users are required to consider
mitigating various threats, such as correlation of activities over
time, location tracking, device-specific vulnerability exploitation,
and address scanning. However, IPv6-over-NFC uses a random (but
stable) identifier (RID) [RFC7217] as an IPv6 interface identifier,
and NFC applications use short-lived connections, and a different
address is used for each connection, where the latter is of extremely
short duration.
8. Acknowledgements
We are grateful to the members of the IETF 6lo working group.
Michael Richardson, Suresh Krishnan, Pascal Thubert, Carsten Bormann,
Alexandru Petrescu, James Woodyatt, Dave Thaler, Samita Chakrabarti,
Gabriel Montenegro, Erik Kline and Carles Gomez Montenegro have
provided valuable feedback for this document.
9. References
9.1. Normative References
[LLCP-1.4] NFC Forum, "NFC Logical Link Control Protocol, Version
1.4", NFC Forum Technical Specification , January 2021,
<https://nfc-forum.org/build/specifications>.
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[NAP-1.0] NFC Forum, "NFC Authentication Protocol Candidate
Technical Specification, Version 1.0", NFC Forum Technical
Specification , December 2020,
<https://nfc-forum.org/build/specifications>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/info/rfc4086>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862,
DOI 10.17487/RFC4862, September 2007,
<https://www.rfc-editor.org/info/rfc4862>.
[RFC4919] Kushalnagar, N., Montenegro, G., and C. Schumacher, "IPv6
over Low-Power Wireless Personal Area Networks (6LoWPANs):
Overview, Assumptions, Problem Statement, and Goals",
RFC 4919, DOI 10.17487/RFC4919, August 2007,
<https://www.rfc-editor.org/info/rfc4919>.
[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, DOI 10.17487/RFC4944, September 2007,
<https://www.rfc-editor.org/info/rfc4944>.
[RFC6282] Hui, J., Ed. and P. Thubert, "Compression Format for IPv6
Datagrams over IEEE 802.15.4-Based Networks", RFC 6282,
DOI 10.17487/RFC6282, September 2011,
<https://www.rfc-editor.org/info/rfc6282>.
[RFC6775] Shelby, Z., Ed., Chakrabarti, S., Nordmark, E., and C.
Bormann, "Neighbor Discovery Optimization for IPv6 over
Low-Power Wireless Personal Area Networks (6LoWPANs)",
RFC 6775, DOI 10.17487/RFC6775, November 2012,
<https://www.rfc-editor.org/info/rfc6775>.
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[RFC7136] Carpenter, B. and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, DOI 10.17487/RFC7136,
February 2014, <https://www.rfc-editor.org/info/rfc7136>.
[RFC7217] Gont, F., "A Method for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217,
DOI 10.17487/RFC7217, April 2014,
<https://www.rfc-editor.org/info/rfc7217>.
[RFC7400] Bormann, C., "6LoWPAN-GHC: Generic Header Compression for
IPv6 over Low-Power Wireless Personal Area Networks
(6LoWPANs)", RFC 7400, DOI 10.17487/RFC7400, November
2014, <https://www.rfc-editor.org/info/rfc7400>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8200] Deering, S., Hinden, R., and RFC Publisher, "Internet
Protocol, Version 6 (IPv6) Specification", STD 86,
RFC 8200, DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC8505] Thubert, P., Ed., Nordmark, E., Chakrabarti, S., and C.
Perkins, "Registration Extensions for IPv6 over Low-Power
Wireless Personal Area Network (6LoWPAN) Neighbor
Discovery", RFC 8505, DOI 10.17487/RFC8505, November 2018,
<https://www.rfc-editor.org/info/rfc8505>.
9.2. Informative References
[ECMA-340] "Near Field Communication - Interface and Protocol (NFCIP-
1) 3rd Ed.", ECMA International , June 2013,
<https://www.ecma-international.org/wp-content/uploads/
ECMA-340_3rd_edition_june_2013.pdf>.
[IANA-6LoWPAN]
Internet Assigned Numbers Authority (IANA), "IPv6 Low
Power Personal Area Network Parameters", 3 December 2021,
<https://www.iana.org/assignments/_6lowpan-parameters>.
[IEEE802.15.4]
IEEE Computer Society, "IEEE Standard for Low-Rate
Wireless Networks, IEEE Std. 802.15.4-2020", IEEE , July
2020, <https://standards.ieee.org/ieee/802.15.4/7029/>.
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[RFC3756] Nikander, P., Ed., Kempf, J., and E. Nordmark, "IPv6
Neighbor Discovery (ND) Trust Models and Threats",
RFC 3756, DOI 10.17487/RFC3756, May 2004,
<https://www.rfc-editor.org/info/rfc3756>.
Authors' Addresses
Younghwan Choi (editor)
Electronics and Telecommunications Research Institute
218 Gajeongno, Yuseung-gu
Daejeon
34129
South Korea
Phone: +82 42 860 1429
Email: yhc@etri.re.kr
Yong-Geun Hong
Daejon University
62 Daehak-ro, Dong-gu
Daejeon
34520
South Korea
Phone: +82 42 280 4841
Email: yonggeun.hong@gmail.com
Joo-Sang Youn
DONG-EUI University
176 Eomgwangno Busan_jin_gu
Busan
614-714
South Korea
Phone: +82 51 890 1993
Email: joosang.youn@gmail.com
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